A cargo deck for an aircraft is known, for example, from the patents DE-AS-21 62 042 and U.S. Pat. No. 3,693,919. The cargo deck comprises floor beams or an equivalent carrier construction, on which are provided floor panels or floor sections, ball mats, roller tracks, latches, roller drive units or other such transport devices for conveying and fixing in position pallets, containers or similar objects. That is, cargo decks of this kind simultaneously comprise both the transport means and the devices needed to lock the cargo into place, and hence constitute a complete transport system, along which the traffic flows steadily.
During the loading process, rainwater, snow or ice is likely to be brought into the cargo space along with the items of freight. To dispose of this water, the ball mats, roller tracks and sometimes also the roller drive units are provided with drainage devices, such as are known for instance from the patent DE 197 24 941 C2. When parts of the transport apparatus are being replaced, e.g., a ball mat with defective systems or the cargo deck must be reconstructed in order to store certain objects in a better way, considerable effort is required if the drainage devices likewise have to be rearranged.
Furthermore, the cargo-loading area must be an essentially tightly enclosed system so that if a fire should break out, the fire can be extinguished with halon. That is, the gas cannot be allowed to flow freely down into the bilge space, and this likewise necessitates considerable sealing work when transport devices are replaced or the cargo deck is reconstructed.